Things I vaguely remember through the haze:
You will hurt all over (labour is really hard physical work, so all your muscles will be stiff), and going to the loo will be scary because it is likely to hurt. Poos become a big deal for the first few weeks. You will bleed a lot at first, more than a heavy period for the first couple of days.
For most people, breastfeeding takes time to get right, and the first couple of weeks are spent worrying that you are doing it all wrong, with lots of crying.
Every time you think you are ready to leave the house, the baby will either want to eat, or do a poo.
Many newborns will only sleep if someone is holding them.
You won't have the faintest idea what you are doing, or what the baby needs, or why s/he is crying. You will learn by trial and error. You will be exhausted from the sheer amount of new stuff you are learning to do. It's a bit like being dumped in a country where you don't speak the language and having to learn how to communicate.
It might literally, physically hurt you when your baby cries (not everyone gets this).
Lots of people respond to the chaos and uncertainty by drawing up lots of charts and schedules. You will look back and think it's crazy, but it makes perfect sense at the time.
Sometimes, newborns will sleep for five hours at a time. At other times, they will only sleep in chunks of ten minutes. They will have days where they do nothing but feed for hours at a time.
The first 6-8 weeks are really intense, but after that you will know what you are doing, although you won't realise that you know what you are doing and will feel like a big fraud.
It's ok to think of your new baby as a sort of very high-maintenance pet. They don't interact much at first.
If you breastfeed, the poo smells nice.
None of the other parents at baby groups know what they are doing either.
You will spend most of your time trapped under a sleeping or feeding baby.